Cannot Get JSON for the JavaScript Object

Question

I'm creating a JS object like this

var eleDetailsTop = new Array();

var j = 0;
var id = "ele"+j;
eleDetailsTop[id] = {id: id, size : "40%", sizeLabel : 12, type : "image", title : "Image"};

Now, I'm trying to convert this object to a JSON...

var fields = JSON.stringify(eleDetailsTop);

So, my problem is, this only gives an empty result.

Here is what I got when I debugged with FireBug

As you can see there is another object called wrappedJSobject inside this. If you checked inside it, you can see another wrappedJSobject as so on...

Why is this ? Why is this weird ?

What does that mean to have `eleDetailsTop[id]` when `id` is not a number? — Omri Aharon, Feb 05 '16 at 20:26
You made `eleDetailsTop` an array, yet you populate it as if it's an object literal. It looks as if you want the array to be associative which is technically prohibited. — zer00ne, Feb 05 '16 at 20:30

Yuriy Galanter · Accepted Answer · 2016-02-05T20:33:31.033

1

You're creating an array and assigning it alphanumeric property. Try this:

var j = 0;
var id = "ele"+j;
eleDetailsTop[j] = {id: id, size : "40%", sizeLabel : 12, type : "image", title : "Image"};

EDIT: If you do want to use id as property - defined eleDetailsTop as object:

var eleDetailsTop = {};

edited Feb 05 '16 at 20:33

answered Feb 05 '16 at 20:27

Yuriy Galanter

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Thanks, But I want the index using `id` Not with just `j`. The index should be a string like `eleDetailsTop['ele2']`.. Is that possible ? – Tharindu Thisarasinghe Feb 05 '16 at 20:31
1

@TharinduLucky then declare `var eleDetailsTop = {};`as an object. – Yuriy Galanter Feb 05 '16 at 20:31
Thanks! I din't know that :) Anyway, I declare the object like you said, but the error still looks same.. :( – Tharindu Thisarasinghe Feb 05 '16 at 20:41
@TharinduLucky: Impossible. – Felix Kling Feb 05 '16 at 20:43
1

@TharinduLucky works here: https://jsfiddle.net/r4zh0tgt/ – Yuriy Galanter Feb 05 '16 at 20:46
1

Yeah, my bad. It's working :) Thanks all :) – Tharindu Thisarasinghe Feb 05 '16 at 20:49

score 1 · Answer 2 · answered Feb 05 '16 at 20:31

1

If you do:

var eleDetailsTop = {};

Then you can assign properties like

eleDetailsTop[id] = {}

But if you really need the array... that won't work because there's no associative arrays in js technically (they're objects).

<script>

    var test = {};

    test['iam1234'] = {};

    console.log(test);

</script>

answered Feb 05 '16 at 20:31

dmgig

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Define "work". It's absolutely possible to assign arbitrary properties to arrays, but you won't be able to include those properties when converted to JSON. – Felix Kling Feb 05 '16 at 20:42
By "work", I was thinking he wouldn't be able to use Array methods like forEach, but You are absolutely correct, it does "work" like a normal array (aside from the JSON issue). – dmgig Feb 05 '16 at 20:49

Cannot Get JSON for the JavaScript Object

2 Answers2